Air INFINITI QX56 2004 Factory Service Manual

REAR VIEW MONITOR
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Revision: August 20072004 QX56
Power Supply and Ground Circuit InspectionEKS007RB
1. CHECK FUSES
Check for blown rear view camera system fuses.
OK or NG
OK >> GO TO 2.
NG >> If fuse is blown, be sure to eliminate cause of problem before installing new fuse. Refer to PG-4,
"POWER SUPPLY ROUTING CIRCUIT" .
2. CHECK POWER SUPPLY CIRCUIT
1. Disconnect rear view camera control unit connector.
2. Check voltage between rear view camera control unit and
ground.
OK or NG
OK >> GO TO 3.
NG >> Check harness for open between rear view camera control unit and fuse.
3. CHECK REAR VIEW CAMERA CONTROL UNIT GROUND CIRCUIT
1. Turn ignition switch OFF.
2. Check continuity between rear view camera control unit harness
connector B73 terminal 3 (B) and ground.
OK or NG
OK >> GO TO 4.
NG >> Repair harness or connector.
4. CHECK REAR VIEW CAMERA GROUND CIRCUIT
1. Disconnect rear view camera connector.
2. Check continuity between rear view camera harness connector
D504 terminal 2 (B) and ground.
OK or NG
OK >> Inspection End.
NG >> Repair harness or connector.
Unit Power source Fuse No.
Rear view camera control unitBattery 31
Ignition switch ACC or ON 4
Te r m i n a l s
OFF ACC (+)
(–)
ConnectorTe r m i n a l
(Wire color)
B731 (Y) Ground Battery voltage Battery voltage
2 (V) Ground 0V Battery voltage
WKIA2027E
Continuity should exist.
SKIA5081E
Continuity should exist.
SKIA5082E

REAR VIEW MONITOR
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4. CHECK DISPLAY CONTROL UNIT CIRCUIT
1. Turn ignition switch OFF.
2. Disconnect display control unit connector.
3. Check continuity between rear view camera control unit harness
connector B73 terminal 5 (BR) and display control unit harness
connector M94 terminal 8 (BR).
4. Check continuity between rear view camera control unit harness
connector B73 terminal 5 (BR) and ground.
OK or NG
OK >> Replace display control unit. Refer to AV-158, "Removal and Installation of Display Control Unit" .
NG >> Repair harness or connector.
5. CHECK AV CONTROL SIGNAL
1. Turn ignition switch OFF.
2. Connect rear view camera control unit connector.
3. Shift A/T selector lever to R position.
4. Check voltage between rear view camera control unit harness
connector B73 terminal 5 (BR) and ground.
OK or NG
OK >> GO TO 6.
NG >> Replace rear view camera control unit. Refer to DI-88,
"Removal and Installation of Rear View Camera Control
Unit" .
6. CHECK REAR VIEW CAMERA OPEN CIRCUIT
1. Turn ignition switch OFF.
2. Disconnect rear view camera connector.
3. Check continuity between rear view camera control unit harness
connector B73 terminal 8 (Y) and rear view camera harness
connector D504 terminal 1 (Y).
4. Check continuity between rear view camera control unit harness
connector B73 terminal 9 and rear view camera harness con-
nector D504 terminal 4.
5. Check continuity between rear view camera control unit harness connector B73 terminal 10 (G) and rear
view camera harness connector D504 terminal 3 (G).
OK or NG
OK >> GO TO 7.
NG >> Repair harness or connector.Continuity should exist.
Continuity should not exist.
SKIA7149E
Voltage : Approx. 0V
SKIA7150E
Continuity should exist.
Continuity should exist.
Continuity should exist.
SKIA5095E

DI-86
REAR VIEW MONITOR
Revision: August 20072004 QX56
7. CHECK REAR VIEW CAMERA SHORT CIRCUIT
1. Check continuity between rear view camera control unit harness
connector B73 terminal 8 (Y) and ground.
2. Check continuity between rear view camera control unit harness
connector B73 terminal 9 and ground.
3. Check continuity between rear view camera control unit harness
connector B73 terminal 10 (G) and ground.
OK or NG
OK >> GO TO 8.
NG >> Repair harness on connector.
8. CHECK POWER SUPPLY AND GROUND CIRCUIT
Check power supply and ground circuit. Refer to DI-83, "
Power Supply and Ground Circuit Inspection" .
OK or NG
OK >> GO TO 9.
NG >> Repair or replace power supply or ground circuit.
9. CHECK REAR VIEW CAMERA CONTROL UNIT OUTPUT SIGNAL
1. Connect rear view camera control unit connector.
2. Turn ignition switch ON.
3. Shift A/T selector lever to R position.
4. Check voltage between rear view camera control unit harness
connector B73 terminal 8 (Y) and ground.
OK or NG
OK >> GO TO 10.
NG >> Replace the rear view camera control unit. Refer to DI-
88, "Removal and Installation of Rear View Camera
Control Unit" . Continuity should not exist.
Continuity should not exist.
Continuity should not exist.
SKIA5098E
Voltage : Approx. 6V
SKIA5099E

REAR VIEW MONITOR
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10. CHECK REAR VIEW CAMERA SIGNAL
1. Connect rear view camera connector.
2. Turn ignition switch ON.
3. Shift A/T selector lever to R position.
4. Check voltage signal between rear view camera control unit har-
ness connector B73 terminal 10 (G) and ground.
OK or NG
OK >> GO TO 11.
NG >> Replace the rear view camera. Refer to DI-88, "
Removal and Installation of Rear View Camera" .
11 . CHECK COMPOSITE SIGNAL OPEN OR SHORT CIRCUIT
1. Turn ignition switch OFF.
2. Disconnect rear view camera control unit connector and display
unit connector.
3. Check continuity between rear view camera control unit harness
connector B73 terminal 12 (W) and display unit harness connec-
tor M93 terminal 15 (W).
4. Check continuity between rear view camera control unit harness
connector B73 terminal 12 (W) and ground.
OK or NG
OK >> GO TO 12.
NG >> Repair harness or connector.
12. CHECK COMPOSITE SIGNAL GROUND CIRCUIT
1. Check continuity between rear view camera control unit harness
connector B73 terminal 11 and display unit harness connector
M93 terminal 4.
2. Check continuity between rear view camera control unit harness
connector B73 terminal 11 and ground.
OK or NG
OK >> GO TO 13.
NG >> Repair harness or connector.10 (G) - Ground:
SKIA5100E
SKIA4894E
Continuity should exist.
Continuity should not exist.
WKIA1825E
Continuity should exist.
Continuity should not exist.
WKIA1826E

EC-1
ENGINE CONTROL SYSTEM
B ENGINE
CONTENTS
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SECTION EC
A
EC
Revision: August 20072004 QX56 INDEX FOR DTC ........................................................ 8
Alphabetical Index .................................................... 8
DTC No. Index ....................................................... 12
PRECAUTIONS ........................................................ 16
Precautions for Supplemental Restraint System
(SRS) “AIR BAG” and “SEAT BELT PRE-TEN-
SIONER” ................................................................ 16
On Board Diagnostic (OBD) System of Engine and
A/T .......................................................................... 16
Precaution .............................................................. 16
Wiring Diagrams and Trouble Diagnosis ................ 19
PREPARATION ......................................................... 20
Special Service Tools ............................................. 20
Commercial Service Tools ...................................... 22
ENGINE CONTROL SYSTEM .................................. 23
System Diagram ..................................................... 23
Vacuum Hose Drawing ........................................... 24
System Chart ......................................................... 25
Multiport Fuel Injection (MFI) System .................... 26
Electronic Ignition (EI) System ............................... 28
Nissan Torque Demand (NTD) Control System ..... 29
Air Conditioning Cut Control ................................... 30
Fuel Cut Control (at No Load and High Engine
Speed) .................................................................... 30
CAN communication .............................................. 31
BASIC SERVICE PROCEDURE .............................. 32
Idle Speed and Ignition Timing Check .................... 32
Idle Speed/Ignition Timing/Idle Mixture Ratio
Adjustment ............................................................. 33
Accelerator Pedal Released Position Learning ...... 44
Throttle Valve Closed Position Learning ................ 44
Idle Air Volume Learning ........................................ 44
Fuel Pressure Check .............................................. 46
ON BOARD DIAGNOSTIC (OBD) SYSTEM ............ 49
Introduction ............................................................ 49
Two Trip Detection Logic ........................................ 49
Emission-related Diagnostic Information ................ 50
IVIS (Infiniti Vehicle Immobilizer System — NATS) ... 63
Malfunction Indicator Lamp (MIL) ........................... 63
OBD System Operation Chart ................................ 66TROUBLE DIAGNOSIS ............................................ 71
Trouble Diagnosis Introduction ............................... 71
DTC Inspection Priority Chart ................................. 76
Fail-safe Chart ........................................................ 77
Basic Inspection ..................................................... 79
Symptom Matrix Chart ............................................ 84
Engine Control Component Parts Location ............ 88
Circuit Diagram ....................................................... 94
ECM Harness Connector Terminal Layout ............. 96
ECM Terminals and Reference Value ..................... 96
CONSULT-II Function ...........................................103
Generic Scan Tool (GST) Function .......................116
CONSULT-II Reference Value in Data Monitor .....118
Major Sensor Reference Graph in Data Monitor
Mode .....................................................................121
TROUBLE DIAGNOSIS - SPECIFICATION VALUE .123
Description ............................................................123
Testing Condition ..................................................123
Inspection Procedure ............................................123
Diagnostic Procedure ...........................................124
TROUBLE DIAGNOSIS FOR INTERMITTENT INCI-
DENT .......................................................................127
Description ............................................................127
Diagnostic Procedure ...........................................127
POWER SUPPLY AND GROUND CIRCUIT ...........128
Wiring Diagram .....................................................128
Diagnostic Procedure ...........................................129
Ground Inspection ................................................133
DTC U1000, U1001 CAN COMMUNICATION LINE .135
Description ............................................................135
On Board Diagnosis Logic ....................................135
DTC Confirmation Procedure ...............................135
Wiring Diagram .....................................................136
Diagnostic Procedure ...........................................137
DTC P0037, P0038, P0057, P0058 HO2S2 HEATER .138
Description ............................................................138
CONSULT-II Reference Value in Data Monitor Mode
.138
On Board Diagnosis Logic ....................................138
DTC Confirmation Procedure ...............................139

EC-7
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ECA
Revision: August 20072004 QX56 Component Inspection ......................................... 582
Removal and Installation ...................................... 582
IGNITION SIGNAL .................................................. 583
Component Description ........................................ 583
Wiring Diagram .................................................... 584
Diagnostic Procedure ........................................... 589
Component Inspection ......................................... 593
Removal and Installation ...................................... 594
INJECTOR CIRCUIT ............................................... 595
Component Description ........................................ 595
CONSULT-II Reference Value in Data Monitor Mode
. 595
Wiring Diagram .................................................... 596
Diagnostic Procedure ........................................... 597
Component Inspection ......................................... 600
Removal and Installation ...................................... 600
FUEL PUMP CIRCUIT ............................................ 601
Description ........................................................... 601
CONSULT-II Reference Value in Data Monitor Mode
. 601
Wiring Diagram .................................................... 602
Diagnostic Procedure ........................................... 603
Component Inspection ......................................... 606
Removal and Installation ...................................... 606
REFRIGERANT PRESSURE SENSOR ................. 607
Component Description ........................................ 607
Wiring Diagram .................................................... 608
Diagnostic Procedure ........................................... 609
Removal and Installation ....................................... 611
ELECTRICAL LOAD SIGNAL ................................ 612
Description ........................................................... 612
CONSULT-II Reference Value in Data Monitor Mode
. 612
Diagnostic Procedure ........................................... 612
ICC BRAKE SWITCH ............................................. 613
Component Description ........................................ 613
CONSULT-II Reference Value in Data Monitor Mode
. 613
Wiring Diagram .................................................... 614
Diagnostic Procedure ........................................... 615
Component Inspection ......................................... 619
ASCD BRAKE SWITCH ......................................... 621
Component Description ........................................ 621CONSULT-II Reference Value in Data Monitor Mode
.621
Wiring Diagram .....................................................622
Diagnostic Procedure ...........................................623
Component Inspection ..........................................627
ASCD INDICATOR ..................................................628
Component Description ........................................628
CONSULT-II Reference Value in Data Monitor Mode
.628
Wiring Diagram .....................................................629
Diagnostic Procedure ...........................................630
MIL AND DATA LINK CONNECTOR ......................631
Wiring Diagram .....................................................631
EVAPORATIVE EMISSION SYSTEM .....................633
Description ............................................................633
Component Inspection ..........................................636
Removal and Installation ......................................637
How to Detect Fuel Vapor Leakage ......................637
ON BOARD REFUELING VAPOR RECOVERY
(ORVR) ....................................................................640
System Description ...............................................640
Diagnostic Procedure ...........................................641
Component Inspection ..........................................643
POSITIVE CRANKCASE VENTILATION ...............645
Description ............................................................645
Component Inspection ..........................................645
AUTOMATIC SPEED CONTROL DEVICE (ASCD) .647
System Description ...............................................647
Component Description ........................................648
SERVICE DATA AND SPECIFICATIONS (SDS) ....649
Fuel Pressure .......................................................649
Idle Speed and Ignition Timing .............................649
Calculated Load Value ..........................................649
Mass Air Flow Sensor ...........................................649
Intake Air Temperature Sensor .............................649
Engine Coolant Temperature Sensor ...................649
A/F Sensor 1 Heater .............................................649
Heated Oxygen sensor 2 Heater ..........................649
Crankshaft Position Sensor (POS) .......................649
Camshaft Position Sensor (PHASE) ....................649
Throttle Control Motor ...........................................649
Injector ..................................................................650
Fuel Pump ............................................................650

EC-16Revision: August 2007
PRECAUTIONS
2004 QX56
PRECAUTIONSPFP:00001
Precautions for Supplemental Restraint System (SRS) “AIR BAG” and “SEAT
BELT PRE-TENSIONER”
UBS00GZ5
The Supplemental Restraint System such as “AIR BAG” and “SEAT BELT PRE-TENSIONER”, used along
with a front seat belt, helps to reduce the risk or severity of injury to the driver and front passenger for certain
types of collision. This system includes seat belt switch inputs and dual stage front air bag modules. The SRS
system uses the seat belt switches to determine the front air bag deployment, and may only deploy one front
air bag, depending on the severity of a collision and whether the front occupants are belted or unbelted.
Information necessary to service the system safely is included in the SRS and SB section of this Service Man-
ual.
WAR NIN G:

To avoid rendering the SRS inoperative, which could increase the risk of personal injury or death
in the event of a collision which would result in air bag inflation, all maintenance must be per-
formed by an authorized NISSAN/INFINITI dealer.

Improper maintenance, including incorrect removal and installation of the SRS, can lead to per-
sonal injury caused by unintentional activation of the system. For removal of Spiral Cable and Air
Bag Module, see the SRS section.

Do not use electrical test equipment on any circuit related to the SRS unless instructed to in this
Service Manual. SRS wiring harnesses can be identified by yellow and/or orange harnesses or
harness connectors.
On Board Diagnostic (OBD) System of Engine and A/TUBS00GZ6
The ECM has an on board diagnostic system. It will light up the malfunction indicator lamp (MIL) to warn the
driver of a malfunction causing emission deterioration.
CAUTION:

Be sure to turn the ignition switch OFF and disconnect the negative battery cable before any
repair or inspection work. The open/short circuit of related switches, sensors, solenoid valves,
etc. will cause the MIL to light up.

Be sure to connect and lock the connectors securely after work. A loose (unlocked) connector will
cause the MIL to light up due to the open circuit. (Be sure the connector is free from water, grease,
dirt, bent terminals, etc.)

Certain systems and components, especially those related to OBD, may use a new style slide-
locking type harness connector. For description and how to disconnect, refer to PG-68, "
HAR-
NESS CONNECTOR" .

Be sure to route and secure the harnesses properly after work. The interference of the harness
with a bracket, etc. may cause the MIL to light up due to the short circuit.

Be sure to connect rubber tubes properly after work. A misconnected or disconnected rubber tube
may cause the MIL to light up due to the malfunction of the EVAP system or fuel injection system,
etc.

Be sure to erase the unnecessary malfunction information (repairs completed) from the ECM and
TCM (Transmission control module) before returning the vehicle to the customer.
PrecautionUBS00GZ7

Always use a 12 volt battery as power source.

Do not attempt to disconnect battery cables while engine is
running.

Before connecting or disconnecting the ECM harness con-
nector, turn ignition switch OFF and disconnect negative
battery cable. Failure to do so may damage the ECM
because battery voltage is applied to ECM even if ignition
switch is turned OFF.

Before removing parts, turn ignition switch OFF and then
disconnect battery ground cable.
SEF 2 89 H

PRECAUTIONS
EC-17
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EC
Revision: August 20072004 QX56

Do not disassemble ECM.

If a battery cable is disconnected, the memory will return to
the ECM value.
The ECM will now start to self-control at its initial value.
Engine operation can vary slightly when the terminal is dis-
connected. However, this is not an indication of a malfunc-
tion. Do not replace parts because of a slight variation.

When connecting ECM harness connector, fasten it
securely with a lever as far as it will go as shown in the fig-
ure.

When connecting or disconnecting pin connectors into or
from ECM, take care not to damage pin terminals (bend or
break).
Make sure that there are not any bends or breaks on ECM
pin terminal, when connecting pin connectors.

Securely connect ECM harness connectors.
A poor connection can cause an extremely high (surge)
voltage to develop in coil and condenser, thus resulting in
damage to ICs.

Keep engine control system harness at least 10 cm (4 in)
away from adjacent harness, to prevent engine control sys-
tem malfunctions due to receiving external noise, degraded
operation of ICs, etc.

Keep engine control system parts and harness dry.

Before replacing ECM, perform ECM Terminals and Refer-
ence Value inspection and make sure ECM functions prop-
erly. Refer to EC-96, "
ECM Terminals and Reference Value"
.

Handle mass air flow sensor carefully to avoid damage.

Do not disassemble mass air flow sensor.

Do not clean mass air flow sensor with any type of deter-
gent.

Do not disassemble electric throttle control actuator.

Even a slight leak in the air intake system can cause seri-
ous incidents.

Do not shock or jar the camshaft position sensor (PHASE), crankshaft position sensor (POS).
PBIB11 64 E
BBIA0387E
PBIB0090E
MEF040D

EC-18Revision: August 2007
PRECAUTIONS
2004 QX56

After performing each TROUBLE DIAGNOSIS, perform DTC
Confirmation Procedure or Overall Function Check.
The DTC should not be displayed in the DTC Confirmation
Procedure if the repair is completed. The Overall Function
Check should be a good result if the repair is completed.

When measuring ECM signals with a circuit tester, never
allow the two tester probes to contact.
Accidental contact of probes will cause a short circuit and
damage the ECM power transistor.

Do not use ECM ground terminals when measuring input/
output voltage. Doing so may result in damage to the ECM's
transistor. Use a ground other than ECM terminals, such as
the ground.

B1 indicates the bank 1, B2 indicates the bank 2 as shown
in the figure.
SEF 2 17 U
SEF 3 48 N
PBIB11 44 E

EC-20Revision: August 2007
PREPARATION
2004 QX56
PREPARATIONPFP:00002
Special Service ToolsUBS00GZ9
The actual shapes of Kent-Moore tools may differ from those of special service tools illustrated here.
Tool number
(Kent-Moore No.)
Tool nameDescription
EG17650301
(J-33984-A)
Radiator cap tester
adapterAdapting radiator cap tester to radiator cap and ra-
diator filler neck
a: 28 (1.10) dia.
b: 31.4 (1.236) dia.
c: 41.3 (1.626) dia.
Unit: mm (in)
KV10117100
(J-36471-A)
Heated oxygen sensor
wrenchLoosening or tightening heated oxygen sensors
with 22 mm (0.87 in) hexagon nut
KV10114400
(J-38365)
Heated oxygen sensor
wrenchLoosening or tightening heated oxygen sensors
a: 22 mm (0.87 in)
(J-44626)
Air fuel ratio (A/F) sen-
sor wrenchLoosening or tightening air fuel ratio (A/F) sensor 1
(J-44321)
Fuel pressure gauge
kitChecking fuel pressure
(J-44321-6)
Fuel pressure adapterConnecting fuel pressure gauge to quick connec-
tor type fuel lines.
(J-45488)
Quick connector re-
leaseRemove fuel tube quick connectors in engine
room.
S-NT564
S-NT379
S-NT636
LEM054
LEC642
LBIA0376E
PBIC0198E